This invention relates to apparatus for supporting an elongated tool-handling boom and, in particular, to apparatus for preventing a tool-handling boom from being damaged in the event the boom becomes fouled with an obstacle while in use.
Most tool-handling booms presently used for conditioning materials in furnaces or the like are relatively rigid structures that are incapable of absorbing shock-like loads which are typically generated when the boom strikes or becomes hung-up on obstacles within the furnace. Many of the newer furnaces now on-line or being built for reclaiming scrap metals contain relatively large melting pits or beds which provide for a more efficient operation. Consequently, the boom needed to handle the material conditioning tool within the furnace must be of considerable length. This, in turn, correspondingly magnifies the effects of stresses or loads induced in the boom in the event it, or the tool secured thereto, is forcefully brought down upon some type of solid instrumentality. Because of its length and its mass, the boom can be easily damaged to a point where it is rendered incapable of carrying out the task for which it was designed.
In the U.S. Pat. No. 4,045,923 there is disclosed a crane boom arrangement wherein an elongated boom section is slidably mounted upon spring-loaded rollers within a stationary gantry so that the boom can be extended or retracted. The rollers are designed to only support the dead weight of the boom to facilitate the repositioning thereof. Bearing pads are provided which are adapted to move into supporting engagement with the boom when the boom experiences any stress or overloading. This, in effect, causes the entire structure to react as a rigid unit to the load, thus making it susceptible to damage.